Project Summary/Abstract Puerto Rico has the highest incidence of HIV in the U.S and it is apparent that behavioral risk among men who have sex with men (MSM) is a significant contributor to the continuing HIV epidemic on the island. Of all HIV (non AIDS) cases diagnosed in Puerto Rico by November 2010, 67.3% were among men. Nearly one quarter of these (16.5%) described having sex with men as a risk factor and 3.3% documented injecting drug use and having sex with men as a risk factor. Paradoxically, although MSM in Puerto Rico are at heightened risk for STIs and HIV, they are among the least likely to be identified and retained in health services. In large part, their under-representation in health services is a consequence of the multiple of types of stigma to which MSM, particularly HIV+MSM, are subject. Despite the substantial and growing prevalence of HIV and STI among MSM in Puerto Rico, there is very limited assessment of social and behavioral determinants of HIV risk in this group. Moreover, and perhaps as a consequence of the limited epidemiological research among MSM, there is also relatively limited targeted HIV-related programming for this group, particularly HIV+MSM. Building on well established collaboration between researchers at the University of Puerto Rico School of Public Health and the Centro Latinoamericano de Enfermedades de Transmisi?n Sexual (CLETS) (one of the largest, publicly- funded STI clinic in San Juan metropolitan area) and Coa?, Inc. (a community-based organization providing HIV preventions services to MSM in Puerto Rico), the proposed research focuses on the development and pilot test of an intervention that will enhance the ability of young adult (25 to 39) HIV+ MSM in Puerto Rico to manage self-perceived stigma. It is also anticipated that this study will enhance health services utilization and retention in this population and that it will serve as the foundation for the development of future epidemiological and prevention research in this and similarly vulnerable populations.